What do the following two equations represent? $3x+4y = -3$ $-4x+3y = -1$
Answer: Putting the first equation in $y = mx + b$ form gives: $3x+4y = -3$ $4y = -3x-3$ $y = -\dfrac{3}{4}x - \dfrac{3}{4}$ Putting the second equation in $y = mx + b$ form gives: $-4x+3y = -1$ $3y = 4x-1$ $y = \dfrac{4}{3}x - \dfrac{1}{3}$ The slopes are negative inverses of each other, so the lines are perpendicular.